Curtain is making weird moves
Cloth simulations like those usually take a few frames to settle.

It is normal that the first few frames go weird on you: the simulation calculates how the mesh behaves with gravity, and how the pinning affects its shape, based on in its physical characteristics. If there are no more forces acting on it, the movement will eventually stop. 

You can set the cache to start before your scene (like 200 frames) so that by the time the scene starts the curtain has already settled on it's resting postition. 

Other way to have the same result, is just to make your scene start at a later frame, so that the movement is not part of the frames to be rendered.



And one more thing you can fix in the cache section: if your animation is 6000 frames, set the End value of the cache to that frame. Otherwise your simulation will stop at the default frame (which is 250).